This invention relates to a fuel control system for an engine and more particularly to an improved fuel control system for an injected engine.
The importance of providing a proper fuel/air mixture in the combustion chamber are well known. It is desirable to insure that the amount of fuel is only that necessary to achieve proper combustion and power output. Excess amounts of fuel can cause objectionable exhaust gas constituents and emission problems.
In order to provide more accurate control of fuel and better combustion, it has been proposed to employ direct cylinder injection. The amount of fuel injected is determined by the load and/or speed at which the engine is operating. Normally a sensor is employed for sensing either the load and/or speed condition of the engine and this sensor outputs a signal to a control which, in turn, controls the amount of fuel injected to suit the running condition. However, all sensors have certain ranges during which they have optimum sensitivity. When operated outside of their most sensitive range, the output of the sensor is not as indicative of the sensed condition as would be desirable. Since internal combustion engines, particularly those for automotive application, run over wide load and speed ranges, the use of a single sensor for the load condition is not completely satisfactory in providing the requisite fuel control.
It is, therefore, a principal object to this invention to provide an improved fuel control for an internal combustion engine.
It is a further object to this invention is provide a fuel control for an internal combustion engine that will be operative to provide the proper amount of fuel under widely varying running conditions.